Manufacture of inner tubes



1,619,119 March 1 1927' H. H. HASTINGS MANUFACTURE 0F INNER TUBES Filed Jan. 24, 1925 a 10 sets of pinching; to insure the eflicienc of Patented Mar. 1, 1927 9 UNITED STATES HORACE HILLYARD HASTINGS, F QUEBEC. QUEBEC, CANADA.

minnraorunn or (INNER Tunas.

Application filed January to reinforce the tube at the lighter or rimv ortion thereof and thereby minimize the atself healing tubes whereby the plastic ler is forced into the opening made by a puncture; to reduce the quantity of material and as a result lighten the tube without aflect- 1 ing the tensile strength; to economize in the cost of roduction and at the same time increase the output of a factory; to add comfort to the lot of travellers by motor car in the avoidance of delays, and expense through 20 punctures; to further the interests of both motorists and supply persons alike by reason of the quality and serviceability of the tube and generally to provide reliability and durability in an inner tube to a tire at a 2 reasonable sale price and it consists essentially in the novel method employed which is described in detail hereinafter, and in the reinforced tube produced all of which is ointed out in the claim for novelt follow- 30 mg this description and setting orth the specific method and form of tube and the broad conception of the invention, thereby allowing scope for reasonable variations and departures.

he drawings show the various steps in the method and the tube inprocess of manufacture, in Figure 1 the tube wall is shown being formed on the, core with the plastic filling, in Figure 2 the tube wall is shown in the act of turning, in Figure 3 the wall is shown as lapped over for splicing, in Figure 4 the tube is shown with the reinforcing strip covering the overlap, in Figure 5 one section of the mould is shownwith the tube therein, in Figure 6, a cross sectional view of the mould sections, the tube and the steam ring are shown in their assembled state on the line 6-6 in Figure 5. In Figure'7 an enlarged projection of the assembled mould, steam ring and tube is shown in the vicinity of the tube valve and steam inlet, in Figure 8 an enlarged sectional and fragmentary detail of the steam'ring is shown, in Figure 9 a cross sectional view is shown on the line 9-9 in Figure 5.

24, 1925; Serial No. 4,460.

Like numerals of reference indicate corresponding parts in the various figures.

The method is carried out largely with known devices, especially so far as the earlier steps of the process are'concerned, as for instance the tube wall 10 is first built up on a core 11 and containsthe plastic substance 12 between the layers 13 and 14.

The wall 10 as so formed is cured by being vulcanized in a suitable oven or other contrivance as customary, of course this step is usually carried out in large batches, but the one tube will be followed throughout.

The wall 10 after curing is turned so as to make the surface on the core the outsideface and the ends 15 and 16 are then brought together and overlapped, the meeting surfaces having been previously skived at the edges and roughened throughout to take the cement applied for the purpose of holding them together. The binding and reinforcing strip 17, extending transversely beyond the ends of the overlaps, is then applied and the cement applied on previously roughened surfaces. The tube as now constituted with an attached valve 18 is introduced into the mould formed of the'halves- 19 and 20 held together by bolts through the lugs 21 and 22 and gripping therebetween at one side the steam ring 23, which is arc-shaped in cross section and has the steam chamber 24 and the steam inlet 25, as Well as the enclosed assage therethrough for the valve 18. The inlet 25 is connected to-a steam supply and the are wall of the chamber 24 completes the circle of the mould and covers the strip 17 and consequently the overlaps. A suitable safety valve is provided to avoid excess pressure according to well known steam practice.

be introduced in the mould is now inflated, which forces the overlapped joint and covering strip 17 against the steam ring and on turning on the steam the strip, which is only semi-cured and the overlaps are thoroughly cured, and the inner tube completed.

The result of this construction is a tube having a comparatively thick tread side wall and a thinner inner wall therefore the tendency of the latter is to expand along the 0 line of least resistance and to push back on the resisting part, which is already under considerable compression through the turning of the wall, because the outside that was longer presses down on the plestic, and this with the pressure from either end operates the plastic substance to fill made openings in the tire.

What I claim is The herein described process in making inflatable tubes consisting in covering the overlapped transverse edges of the vulcanized inner joint with an annularly extending strip of rubber and cementing the latter to the tube, then introducing the tube into a circumscribed area and inflating and finally applying a hot metal surface enclosed Within said area to the said strip throughout its complete length at one and the same time and thereby merging said strip with the wall of the tube at the joint portion.

Signed at Montreal, Canada, this 20th day of January, 1925.

HORACE HILLYARD rmsrmos'. 

